Search

The destruction of marine soft clays' macropore structure results in large-strain deformation during consolidation, as well as the potential to alter rheological deformation characteristics. A sectionalised regimes rheological model was adopted to describe the structural characteristics under the isotache framework, which led to a nonlinear variation of geometrical boundaries and material properties during consolidation. A semi-analytical theory combining numerical and analytical methods was developed, and the solutions for excess pore water pressure, degree of consolidation, and settlement were derived and computationally programmed. Using parametric analysis, the effects of rheological and structural characteristics on the consolidation behaviour of soft clay were discussed compared to the solutions of other theories. The coefficient of secondary consolidation in the transitional regime has an impact beginning in the middle of primary consolidation. The proposed solutions for degree of consolidation are smaller than the small-strain solutions during the early period of primary consolidation but change larger as consolidation progresses. [ABSTRACT FROM AUTHOR]

Pore water and earth pressures acting on retaining structures are investigated using an efficient coastal double-layered excavation model to determine offshore excavation responses to groundwater fluctuations outside foundation pits. Total pore water pressure includes excess pore water pressure (due to groundwater fluctuations) and steady pore water pressure (due to steady seepage) determined using one-dimensional consolidation theory of double-layered soil and one-dimensional steady-state flow theory, respectively. Rankine's active and passive earth pressures are obtained from pore water pressure. This method is applicable to arbitrary groundwater fluctuation conditions. How physical parameters affect pore water pressure is numerically investigated using examples, demonstrating the method's practicality for calculating pore water and earth pressures. [ABSTRACT FROM PUBLISHER]

A new method for non-linear analysis of foundation beam was presented. Firstly, a piecewise linear function was used to fit the nonlinear p-s curve and a unified relationship between pressure and settlement under foundation beam was set up with an introduced control variable. The energy functional dealing with the deformation of foundation beam was then derived. Combined with the complementarities which drawn from the piecewise linear function, a standard linear complementary model was formed by using parametric variational principle. This model can be solved by a mature programming algorithm known as planning algorithm. Consequently, the non-linear analysis of foundation beam was transformed into computing a standard mathematical model. After the rationality of the proposed method was validated, a detailed solution process for non-linear analysis of foundation beam under concentrated load was presented. On the basis, the difference between linear and non-linear analyses and factors that affect the non-linear calculation results were investigated. It shows that the uneven settlement and the internal bending moment of foundation beam increases when the non-linear effects are considered. Increasing the nonlinearity level of the p-s curve or decreasing the pressure threshold into non-linear section, the non-linear effects become more obvious. Both the load intensity and the relative stiffness of beam to foundation affect the distribution form of displacement in the non-linear analysis of foundation beam. [ABSTRACT FROM AUTHOR]

Abstract: A comprehensive analytical solution is developed in this paper to investigate the torsional vibration of an end bearing pile embedded in a homogeneous poroelastic medium and subjected to a time-harmonic torsional loading. The poroelastic medium is modeled using Biot’s two-phased linear theory and the pile using one-dimensional elastic theory. By using the separation of variables technique, the torsional response of the soil layer is solved first. Then based on perfect contact between the pile and soil, the dynamic response of the pile is obtained in a closed form. Numerical results for torsional impedance of the soil layer are presented first to portray the influence of wave modes, slenderness ratio, pile–soil modulus ratio and poroelastic properties. A comparison with the plane strain theory is performed. The selected numerical results are obtained to analyze the influence of the major parameters on the torsional impedance at the level of the pile head. Finally, the dynamic torsional impedance of this study is compared with that for floating pile in elastic soil. [Copyright &y& Elsevier]